Battery cluster equalization control method and device, equipment and storage medium

Abstract

The invention discloses a battery cluster equalization control method, device and equipment and a storage medium, and relates to the technical field of batteries, and the battery cluster equalization control method comprises the steps: judging whether each battery module is equalized or not through each module voltage of each battery module in a battery cluster, and when it is judged that each battery module is unbalanced, judging whether each battery module is equalized or not; and performing inter-module equalization control on each battery module. And judging whether each module cell is balanced or not through each cell voltage of each module cell in each battery module, and performing inter-cell balance control on each module cell when judging that each module cell is unbalanced. The battery modules and the battery cells of the modules can be subjected to balance control at the same time, so that the situation that the module voltage deviation among the battery modules in the cluster is too large can be better prevented, the service life of the battery cluster is further prolonged, meanwhile, the time spent in the balance process is shorter, and the balance efficiency of the battery cluster is improved. And meanwhile, less time is spent in the balancing process.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cluster balancing control method, device, equipment and storage medium. Background Art

[0002] High-voltage battery clusters are widely used in electric vehicles, industrial and commercial energy storage and other scenarios. They are usually lithium battery clusters. After long-term charge and discharge cycles, the internal resistance, self-discharge rate and other parameters of the lithium battery cells in the module will become more discrete, which will cause imbalance between modules and between internal cells. In the prior art, active and passive balancing is usually performed on battery modules to avoid overcharging or over-discharging between battery modules. However, in actual situations, since the internal resistance of each cell in the battery module may also change, the effect of active and passive balancing of the battery module alone is not ideal and takes a long time. Summary of the invention

[0003] The main purpose of the present application is to provide a battery cluster balancing control method, device, equipment and storage medium, aiming to solve the technical problem of how to further improve the voltage balance of each battery module in a battery cluster.

[0004] To achieve the above object, the present application provides a battery cluster balancing control method, wherein the battery cluster comprises a plurality of battery modules connected in series, each of the battery modules comprises a plurality of module cells connected in series, and the steps of the battery cluster balancing control method include:

[0005] Obtaining the module voltage of each of the battery modules, and obtaining the cell voltage of each of the module cells;

[0006] Based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, determining whether the battery modules are balanced;

[0007] When it is determined that the battery modules are unbalanced, performing inter-module balancing control on the battery modules;

[0008] When performing the inter-module balancing control on each of the battery modules, judging whether the cells of each module are balanced based on the second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module;

[0009] When it is determined that the battery cells of each module are unbalanced, balance control is performed on the battery cells of each module.

[0010] In one embodiment, the step of determining whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages comprises:

[0011] Based on the highest module voltage and the lowest module voltage, obtaining a maximum module voltage difference;

[0012] When the maximum module voltage difference is greater than the first voltage threshold, determining that the battery modules are unbalanced;

[0013] Or, when the maximum module voltage difference is not greater than the first voltage threshold, it is determined that the battery modules are balanced.

[0014] In one embodiment, when it is determined that the battery modules are unbalanced, the step of performing inter-module balancing control on the battery modules includes:

[0015] When determining that each of the battery modules is unbalanced, obtaining a corresponding module voltage average based on each of the module voltages;

[0016] Based on the third voltage threshold, the module voltage average and each module voltage, determining in sequence whether each battery module needs active balancing;

[0017] When it is determined that the battery module needs active balancing, a DCDC module connected to the battery module is controlled to output a preset current to the battery module, so that the battery module performs the inter-module balancing control.

[0018] In one embodiment, when performing the inter-module balancing control on each of the battery modules, the step of judging whether the cells of each module are balanced based on the second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module includes:

[0019] When performing the inter-module balancing control on each of the battery modules, obtaining a maximum cell voltage difference based on the highest cell voltage and the lowest cell voltage;

[0020] When the maximum cell voltage difference is greater than the second voltage threshold, determining that the cell of each module is unbalanced;

[0021] Or, when the maximum cell voltage difference is not greater than the second voltage threshold, it is determined that the cells of each module are balanced.

[0022] In one embodiment, when it is determined that the battery cells of each module are unbalanced, the step of performing battery cell balancing control on the battery cells of each module includes:

[0023] When it is determined that the battery cells of each module are unbalanced, based on the voltages of each battery cell of the corresponding battery module and the lowest battery cell voltage, a relative voltage difference of each battery cell is obtained;

[0024] Based on the relative voltage difference of each battery cell and the second voltage threshold, determining in turn whether each module battery cell needs passive balancing;

[0025] When it is determined that the module cells need passive balancing, the corresponding parallel switch devices of the module cells are controlled to be turned on, and the balancing resistors connected in series with the switch devices are connected to the module cells, so that the module cells can perform the balancing control between the cells.

[0026] In one embodiment, after the step of determining whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, the method further includes:

[0027] When determining that each of the battery modules is balanced, based on each of the battery cell voltages corresponding to the battery module, the highest battery cell voltage, and the lowest battery cell voltage, a maximum battery cell voltage difference and a relative voltage difference of each battery cell are obtained;

[0028] Based on the maximum cell voltage difference, the relative voltage difference of each cell and the second voltage threshold, determining whether each module cell needs passive balancing;

[0029] When it is determined that the module cells need passive balancing, the corresponding parallel switch devices of the module cells are controlled to be turned on, and the balancing resistors connected in series with the switch devices are connected to the module cells, so that the module cells can perform the balancing control between the cells.

[0030] In one embodiment, before the step of determining whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, the step further includes:

[0031] Obtaining the number of cells in each of the battery modules;

[0032] Based on the number of each of the battery cells and the second voltage threshold, the first voltage threshold corresponding to each of the battery modules is determined.

[0033] In addition, to achieve the above objectives, the present application also provides a battery cluster balancing control device, the battery cluster balancing control device comprising:

[0034] A voltage acquisition module, used to acquire the voltage of each module of each battery module in the battery cluster, and acquire the voltage of each cell of each module cell in each of the battery modules;

[0035] An inter-module balance judgment module, used for judging whether the battery modules are balanced based on a first voltage threshold, a highest module voltage and a lowest module voltage among the module voltages;

[0036] An inter-module balancing control module, used for performing inter-module balancing control on each of the battery modules when it is determined that each of the battery modules is unbalanced;

[0037] An inter-cell balancing judgment module, used for judging whether the cells of each module are balanced based on a second voltage threshold, a highest cell voltage and a lowest cell voltage among the cell voltages of each cell of the battery module when performing the inter-module balancing control on each battery module;

[0038] The cell-to-cell balancing control module is used to perform cell-to-cell balancing control on the cell-to-cell of each module when it is determined that the cell-to-cell of each module is unbalanced.

[0039] In addition, to achieve the above-mentioned purpose, the present application also provides a battery cluster balancing control device, which includes: a memory, a processor, and a battery cluster balancing control program stored in the memory and executable on the processor, wherein the battery cluster balancing control program is configured to implement the steps of the battery cluster balancing control method described above.

[0040] In addition, to achieve the above-mentioned purpose, the present application also provides a storage medium, which is a computer-readable storage medium, and a battery cluster balancing control program is stored on the computer-readable storage medium. When the battery cluster balancing control program is executed by a processor, the steps of the battery cluster balancing control method described above are implemented.

[0041] The present application provides a battery cluster balancing control method, device, equipment and storage medium, wherein the steps of the battery cluster balancing control method include: obtaining the module voltages of each battery module, and obtaining the cell voltages of each module cell; judging whether each battery module is balanced based on a first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages; performing inter-module balancing control on each battery module when judging that each battery module is unbalanced; judging whether each module cell is balanced based on a second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module when performing inter-module balancing control on each battery module; performing inter-cell balancing control on each module cell when judging that each module cell is unbalanced. Judging whether each battery module is balanced based on the module voltages of each battery module in the battery cluster, and performing inter-module balancing control on each battery module when judging that each battery module is unbalanced. Then, the cell voltages of the cells in each module in each battery module are used to determine whether the cells in each module are balanced. When it is determined that the cells in each module are unbalanced, the cells in each module are balanced. Since the battery modules and cells in each module can be balanced at the same time, it is possible to better prevent the voltage deviation between the battery modules in the cluster from being too large, further improve the service life of the battery cluster, and also reduce the time spent on the balancing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0043] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0044] Figure 1 A flowchart of the first embodiment of the battery cluster balancing control method of the present application is provided;

[0045] Figure 2 A schematic diagram of the structure of a battery cluster balancing system provided in this application;

[0046] Figure 3 A flow chart of the second embodiment of the battery cluster balancing control method of the present application;

[0047] Figure 4 A flowchart of the third embodiment of the battery cluster balancing control method of the present application is provided;

[0048] Figure 5 This is a schematic diagram of the module structure of a battery cluster balancing control device according to an embodiment of the present application;

[0049] Figure 6 It is a structural schematic diagram of a battery cluster balancing control device according to an embodiment of the present application.

[0050] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0052] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0053] This application proposes a first embodiment of a battery cluster balancing control method, please refer to Figure 1 The battery cluster comprises a plurality of battery modules connected in series, each of the battery modules comprises a plurality of module cells connected in series, and the steps of the battery cluster balancing control method include:

[0054] Step S10, obtaining the module voltage of each of the battery modules, and obtaining the cell voltage of each of the module cells;

[0055] It should be understood that in this embodiment, the execution subject may be a battery cluster management module or a battery cluster balancing control device, or a battery cluster balancing control device with data processing, network communication and program running functions, etc. This embodiment does not specifically limit this.

[0056] It should be noted that, in this embodiment, the method can be specifically applied to a battery cluster balancing system, which can be combined with Figure 2For reference, in the entire battery cluster balancing system, the battery cluster includes a number of battery modules BZ connected in series, and each battery module BZ includes a number of module cells B connected in series. Under ideal conditions, the module voltages corresponding to each battery module BZ are the same, and the cell voltages corresponding to each module cell B are the same. Each battery module BZ is connected to a second DCDC module M2 in a one-to-one correspondence, and each second DCDC module M2 is also connected in parallel through a bus bar, wherein the bus bar is also connected to the positive electrode CB+ of the battery cluster and the negative electrode CB- of the battery cluster through the first DCDC module M1. Each module battery cell B corresponds to a switch device K and a balancing resistor R connected in parallel with the switch device K. The control end of each switch device K can be connected to the corresponding battery management unit BMU (Battery Management Unit, BMU) in the battery cluster management module through the CAN bus or RS485 bus. Each battery management unit BMU can also be connected to the battery control unit BCU (Battery Control Unit, BCU) in the battery cluster management module through the CAN bus or RS485 bus. The control end of the first DCDC module M1 can be connected to the battery control unit BCU through the CAN bus or RS485 bus, and the control end of each second DCDC module M2 can be connected to the corresponding battery management unit BMU in the battery cluster management module through the CAN bus or RS485 bus (not drawn in the figure). Among them, the CAN bus or RS485 bus can enable communication or control between various functional modules or functional units (such as the first DCDC module M1, each second DCDC module M2, each battery control unit BCU and battery management unit BMU). For example, the battery control unit BCU in the battery cluster management module can control the start and stop state of the first DCDC module M1, and each battery management unit BMU in the battery cluster management module can respectively control the start and stop state of each corresponding second DCDC module M2, and information can be transmitted between each battery management unit BMU and the battery control unit BCU. In addition, the battery control unit BCU in the battery cluster management module can also control the first DCDC module M1 according to the voltage at both ends of the battery cluster to dynamically adjust its voltage conversion ratio during operation, so as to convert the dynamically changing voltage at both ends of the battery cluster into a fixed voltage value; at the same time, each battery management unit BMU in the battery cluster management module can also control the corresponding second DCDC module M2 according to the voltage at both ends of the corresponding battery module BZ to dynamically adjust its voltage conversion ratio during operation, so as to convert the fixed voltage value output by the first DCDC module M1 to the bus into another voltage value suitable for charging the corresponding battery module BZ. Through the above closed-loop mechanism, the balancing control can be made more stable and efficient.

[0057] It should be understood that in this embodiment, each module voltage at both ends of each battery module BZ and each cell voltage at both ends of each module cell B inside the battery module BZ can be obtained through each battery management unit BMU.

[0058] Step S20, judging whether the battery modules are balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages;

[0059] It should be noted that the first voltage threshold can be understood as a predicted voltage corresponding to whether it is necessary to turn on the battery module balancing control. In this embodiment, the highest module voltage and the lowest module voltage can be screened out from the module voltages corresponding to the obtained battery modules, and the highest module voltage and the lowest module voltage can be used to judge whether there is an imbalance between the battery modules.

[0060] Step S30, when it is determined that the battery modules are unbalanced, performing inter-module balancing control on the battery modules;

[0061] It is easy to understand that in this embodiment, when it is determined that there is an imbalance in the current battery modules, each battery module can be scanned to screen out the battery modules with low module voltage, and based on the total voltage at both ends of the battery cluster, they are supplemented with power through the first DCDC and the corresponding second DCDC module, so that the module voltages of each battery module are kept consistent, that is, the inter-module balancing control of each battery module is completed.

[0062] Step S40, when performing the inter-module balancing control on each of the battery modules, judging whether the cells of each module are balanced based on the second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module;

[0063] It should be noted that the second voltage threshold can be understood as a predicted voltage corresponding to whether it is necessary to turn on the module cell balancing control. In the present embodiment, when performing inter-module balancing control on each battery module, the highest cell voltage and the lowest cell voltage can be screened out from the cell voltages corresponding to the cells of each module, and the highest cell voltage and the lowest cell voltage can be used to judge whether there is an imbalance between the cells of each module.

[0064] Step S50 , when it is determined that the battery cells of each module are unbalanced, performing battery cell balancing control on the battery cells of each module.

[0065] It is easy to understand that in this embodiment, when it is determined that there is an imbalance in the current module cells, the module cells can be scanned to screen out the module cells with higher cell voltages, and the corresponding module cells can be controlled to discharge, so that the cell voltages of the module cells can be kept consistent, thereby completing the balance control between the module cells.

[0066] The present application provides a battery cluster balancing control method, the steps of which include: obtaining the module voltages of each battery module and obtaining the cell voltages of each module cell; judging whether each battery module is balanced based on a first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages; performing inter-module balancing control on each battery module when judging that each battery module is unbalanced; judging whether each module cell is balanced based on a second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module when performing inter-module balancing control on each battery module; performing inter-cell balancing control on each module cell when judging that each module cell is unbalanced. Judging whether each battery module is balanced based on the module voltages of each battery module in the battery cluster, and performing inter-module balancing control on each battery module when judging that each battery module is unbalanced. Then, the cell voltages of the cells in each module in each battery module are used to determine whether the cells in each module are balanced. When it is determined that the cells in each module are unbalanced, the cells in each module are balanced. Since the battery modules and cells in each module can be balanced at the same time, it is possible to better prevent the voltage deviation between the battery modules in the cluster from being too large, further improve the service life of the battery cluster, and also reduce the time spent on the balancing process.

[0067] Based on the first embodiment of the battery cluster balancing control method of the present application, in the second embodiment of the battery cluster balancing control method of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 3 The step of judging whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages comprises:

[0068] Step S21, obtaining a maximum module voltage difference based on the highest module voltage and the lowest module voltage;

[0069] Step S22, when the maximum module voltage difference is greater than the first voltage threshold, determining that the battery modules are unbalanced;

[0070] Step S23, or, when the maximum module voltage difference is not greater than the first voltage threshold, determining that the battery modules are balanced.

[0071] It should be noted that, in this embodiment, the maximum module voltage difference can be obtained by performing a difference process between the highest module voltage and the lowest module voltage among the obtained module voltages and taking the absolute value. When the maximum module voltage difference exceeds the first voltage threshold, it can be considered that the battery modules currently connected in series may produce overcharge or over-discharge during the charging and discharging process, that is, there is an imbalance between the battery modules. On the contrary, when the maximum module voltage difference does not exceed the first voltage threshold, it can be considered that the battery modules currently connected in series will not produce overcharge or over-discharge during the charging and discharging process, that is, there is no imbalance between the battery modules.

[0072] Further, in this embodiment, when it is determined that the battery modules are unbalanced, the step of performing inter-module balancing control on the battery modules includes:

[0073] Step S31, when it is determined that each of the battery modules is unbalanced, obtaining a corresponding module voltage average based on each of the module voltages;

[0074] Step S32, based on the third voltage threshold, the module voltage average and each module voltage, determining in sequence whether each of the battery modules needs active balancing;

[0075] It should be noted that the third voltage threshold can be understood as the voltage corresponding to the battery module for screening the battery module that needs to start active balancing. In this embodiment, the module voltage average can be obtained by taking the average of the module voltages of each battery module. The module voltages of each battery module can be compared with the module voltage average in turn. When the module voltage is lower than the module voltage average and the absolute value of the difference between the module voltage and the module voltage average is greater than the third voltage average, it means that the module voltage of the current battery module is low, and it is determined that the current battery module needs active balancing.

[0076] Step S33, when it is determined that the battery module needs active balancing, a DCDC module connected to the battery module is controlled to output a preset current to the battery module, so that the battery module performs the inter-module balancing control.

[0077] It is easy to understand that in this embodiment, if it is determined that the corresponding battery module needs to be actively balanced, the DCDC module connected to it can be controlled to be turned on (including the first DCDC module and the second DCDC module, the first DCDC module is turned on first, and then the correspondingly connected second DCDC module is turned on), so as to output a preset current through the battery cluster to replenish the battery module, so that the module voltage of the battery module gradually approaches the module voltage average, and then similar operations are performed on the remaining battery modules in turn, thereby realizing inter-module balancing control of the battery modules.

[0078] It is worth noting that, in this embodiment, if active balancing is not required, all DCDC modules are turned off and do not work.

[0079] Further, in this embodiment, when performing the inter-module balancing control on each of the battery modules, the step of judging whether the battery cells of each module are balanced based on the second voltage threshold, the highest battery cell voltage and the lowest battery cell voltage among the battery cell voltages of the corresponding battery module includes:

[0080] Step S41, when performing the inter-module balancing control on each of the battery modules, obtaining a maximum cell voltage difference based on the highest cell voltage and the lowest cell voltage;

[0081] Step S42, when the maximum cell voltage difference is greater than the second voltage threshold, determining that the cell of each module is unbalanced;

[0082] Step S43, or, when the maximum cell voltage difference is not greater than the second voltage threshold, determining that the cells of each module are balanced.

[0083] It should be noted that, in the present embodiment, the maximum cell voltage difference can be obtained by performing a difference process between the highest cell voltage and the lowest cell voltage among the obtained cell voltages and taking the absolute value. When the maximum cell voltage difference exceeds the second voltage threshold, it can be considered that the cells of the modules connected in series within the current battery module may be overcharged or over-discharged during the charging and discharging process, that is, there is an imbalance between the battery modules. On the contrary, when the maximum cell voltage difference does not exceed the second voltage threshold, it can be considered that the cells of the modules connected in series will not be overcharged or over-discharged during the charging and discharging process, that is, there is no imbalance between the cells of the modules.

[0084] Further, in this embodiment, when it is determined that the battery cells of each module are unbalanced, the step of performing battery cell balancing control on the battery cells of each module includes:

[0085] Step S51, when it is determined that the battery cells of each module are unbalanced, based on the voltages of each battery cell of the corresponding battery module and the lowest battery cell voltage, obtaining the relative voltage difference of each battery cell;

[0086] Step S52, based on the relative voltage difference of each battery cell and the second voltage threshold, determining in turn whether each module battery cell needs passive balancing;

[0087] It should be noted that, in this embodiment, the relative voltage difference of each corresponding cell can be obtained by performing difference processing on the voltage of each cell of each module in the battery module and the minimum cell voltage and taking the absolute value.

[0088] The relative voltage difference of each cell of each module cell can be compared with the lowest cell voltage in turn. When the relative voltage difference of each cell is greater than the second voltage average, it means that the voltage of each cell of each module cell is too high, and it is determined that the current module cells need to be passively balanced.

[0089] Step S53, when it is determined that the module cells need passive balancing, the corresponding parallel switch devices of the module cells are controlled to be turned on, and the balancing resistors connected in series with the switch devices are connected to the module cells, so that the module cells perform the balancing control between the cells.

[0090] It is easy to understand that in the present embodiment, if it is determined that each module cell needs to be passively balanced, the switch device connected to each module cell can be controlled to be turned on, and each balancing resistor can be connected in parallel with each module cell one by one through the turned-on switch device. The module cell with a higher cell voltage can consume power through the parallel balancing resistor to release excess electric energy, so that the cell voltage of the module cell gradually approaches the average of the cell voltages. Subsequently, similar operations are performed on the remaining module cells with higher cell voltages in turn, thereby realizing inter-cell balancing control of the module cells.

[0091] Based on the first embodiment and / or the second embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those of the above-mentioned first and second embodiments can refer to the above introduction, and will not be repeated later. Figure 4 , after the step of judging whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, the method further includes:

[0092] Step S61, when determining whether each of the battery modules is balanced, based on each of the battery cell voltages corresponding to the battery module, the highest battery cell voltage and the lowest battery cell voltage, obtaining a maximum battery cell voltage difference and a relative voltage difference of each battery cell;

[0093] Step S62, judging whether each of the module cells needs passive balancing based on the maximum cell voltage difference, the relative voltage difference of each of the cells and the second voltage threshold;

[0094] It should be noted that, in this embodiment, even if there is no need to perform inter-module balancing control on each battery module, inter-cell balancing control can still be performed on the battery cells of each module inside each battery module.

[0095] It is easy to understand that in this embodiment, if it is determined that each battery module is balanced, there is no need to perform inter-module balancing control. At this time, the cell voltages of each module cell in the battery module can be screened to screen out the maximum cell voltage and the minimum cell voltage, and the corresponding maximum cell voltage difference is obtained through the maximum cell voltage and the minimum cell voltage, and the corresponding relative voltage difference of each cell is obtained through each cell voltage and the minimum cell voltage. When the maximum cell voltage difference is greater than the second voltage threshold and the relative voltage difference of each cell is greater than the minimum cell voltage, it is determined that the corresponding module cells need passive balancing. Otherwise, passive balancing is not required.

[0096] Step S63, when it is determined that the module cells need passive balancing, the corresponding parallel switch devices of the module cells are controlled to be turned on, and the balancing resistors connected in series with the switch devices are connected to the module cells, so that the module cells perform the inter-cell balancing control.

[0097] It is easy to understand that in this embodiment, if it is determined that each battery module does not need to be actively balanced and each module cell needs to be passively balanced, the switching devices connected to each module cell can still be controlled to be turned on, and each balancing resistor is connected in parallel with each module cell one by one through the turned-on switching devices. The module cells with higher cell voltages can consume power through the parallel balancing resistors to release excess electric energy, and then similar operations are performed on the remaining module cells with higher cell voltages in turn, thereby achieving inter-cell balancing control of the module cells.

[0098] It is worth noting that, in this embodiment, the inter-module balancing control of each battery module and the inter-cell balancing control of each module battery cell can be performed separately or simultaneously, and the balancing efficiency can be improved when the two are performed simultaneously. When performing inter-module balancing control, the start and stop of the DCDC module (including the first DCDC module and the corresponding second DCDC module) connected to the corresponding battery module is mainly controlled to supplement the power for the battery module with a small module voltage, thereby realizing active balancing; and when performing inter-cell balancing control, the pass state of the switching device connected to the corresponding module battery cell is mainly controlled, so that the module battery cell with a large module voltage is discharged through the parallel balancing resistor, thereby realizing passive balancing. If the two are performed simultaneously, the preset current of the active balancing provided by the DCDC module should be larger than the current of the passive balancing in the original circuit.

[0099] Furthermore, in this embodiment, before the step of judging whether the battery modules are balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, the step further includes:

[0100] Step S201, obtaining the number of battery cells in each module of each battery module;

[0101] Step S202: determining the first voltage threshold corresponding to each of the battery modules based on the number of each of the battery cells and the second voltage threshold.

[0102] It should be noted that, in the present embodiment, the module voltages output by each battery module should theoretically be equal, and the internal structures of each battery module may be the same, each including a number of module cells connected in series. Therefore, for a battery module, it can be understood that its module voltage is obtained by superimposing the voltages of a number of cells. Therefore, the criterion for determining whether the battery module is balanced can also be obtained by superimposing the criterion for determining whether the module cells in the battery module are balanced.

[0103] It is easy to understand that in this embodiment, the number of modules of each battery module and the number of cells of each module in each battery module can be obtained through the battery cluster management module. Therefore, the first voltage threshold for determining battery module imbalance can be obtained by multiplying the number of cells of each module in the battery module by the second voltage threshold for determining module cell imbalance.

[0104] In addition, the present application also proposes a battery cluster balancing control device, please refer to Figure 5 , the battery cluster balancing control device comprises:

[0105] The voltage acquisition module 10 is used to acquire the voltage of each module of each battery module in the battery cluster, and acquire the voltage of each battery cell of each module in each battery module;

[0106] An inter-module balance judgment module 20, configured to judge whether the battery modules are balanced based on a first voltage threshold, a highest module voltage and a lowest module voltage among the module voltages;

[0107] An inter-module balancing control module 30, for performing inter-module balancing control on each of the battery modules when it is determined that the battery modules are unbalanced;

[0108] The inter-cell balancing judgment module 40 is used to judge whether the cells of each module are balanced based on the second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module when performing the inter-module balancing control on each battery module;

[0109] The cell-to-cell balancing control module 50 is used to perform cell-to-cell balancing control on the cell-to-cell of each module when it is determined that the cell-to-cell of each module is unbalanced.

[0110] The battery cluster balancing control device provided in the embodiment of the present application adopts the battery cluster balancing control method in the above embodiment, which can solve the technical problem of how to further improve the voltage balancing of each battery module in the battery cluster. Compared with the prior art, the beneficial effects of the battery cluster balancing control device provided in the embodiment of the present application are the same as the beneficial effects of the battery cluster balancing control method provided in the above embodiment, and other technical features in the battery cluster balancing control device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0111] The present application provides a battery cluster balancing control device, the battery cluster balancing control device comprising: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the battery cluster balancing control method in the above-mentioned embodiment 1.

[0112] Reference below Figure 6 , which shows a schematic diagram of the structure of a battery cluster balancing control device suitable for implementing the embodiment of the present application. The battery cluster balancing control device in the embodiment of the present application may include but is not limited to a fixed terminal such as a vehicle-mounted terminal. Figure 6 The battery cluster balancing control device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0113] like Figure 6As shown, the battery cluster balancing control device may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the battery cluster balancing control device are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 may allow the battery cluster balancing control device to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows a battery cluster balancing control device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have alternatively.

[0114] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0115] The battery cluster balancing control device provided by the present application adopts the battery cluster balancing control method in the above embodiment, which can solve the technical problem of how to further improve the voltage balancing of each battery module in the battery cluster. Compared with the prior art, the beneficial effects of the battery cluster balancing control device provided by the present application are the same as the beneficial effects of the battery cluster balancing control method provided by the above embodiment, and the other technical features in the battery cluster balancing control device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0116] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0117] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0118] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the battery cluster balancing control method in the above-mentioned embodiment.

[0119] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0120] The computer-readable storage medium may be included in the battery cluster balancing control device; or may exist independently without being assembled into the battery cluster balancing control device.

[0121] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the battery cluster balancing control device, the battery cluster balancing control device: obtains each module voltage of each battery module, and obtains each cell voltage of each module cell; determines whether each battery module is balanced based on a first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages; performs inter-module balancing control on each battery module when it is determined that each battery module is unbalanced; when performing inter-module balancing control on each battery module, determines whether each module cell is balanced based on a second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages corresponding to the battery module; and performs inter-cell balancing control on each module cell when it is determined that each module cell is unbalanced.

[0122] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0123] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0124] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0125] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned battery cluster balancing control method, and can solve the technical problem of how to more accurately determine whether the oil pump motor has a speed following failure. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the battery cluster balancing control method provided in the above-mentioned embodiment, and will not be repeated here.

[0126] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A battery cluster balancing control method, characterized in that: The battery cluster comprises a plurality of battery modules connected in series, each of the battery modules comprises a plurality of module cells connected in series, and the steps of the battery cluster balancing control method include: Obtaining the module voltage of each of the battery modules, and obtaining the cell voltage of each of the module cells; Based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, determining whether the battery modules are balanced; When it is determined that the battery modules are unbalanced, performing inter-module balancing control on the battery modules; When performing the inter-module balancing control on each of the battery modules, judging whether the cells of each module are balanced based on the second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module; When it is determined that the battery cells of each module are unbalanced, balance control is performed on the battery cells of each module.

2. The battery cluster balancing control method according to claim 1, characterized in that: The step of judging whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages comprises: Based on the highest module voltage and the lowest module voltage, obtaining a maximum module voltage difference; When the maximum module voltage difference is greater than the first voltage threshold, determining that the battery modules are unbalanced; Or, when the maximum module voltage difference is not greater than the first voltage threshold, it is determined that the battery modules are balanced.

3. The battery cluster balancing control method according to claim 1, characterized in that: When it is determined that the battery modules are unbalanced, the step of performing inter-module balancing control on the battery modules comprises: When determining that each of the battery modules is unbalanced, obtaining a corresponding module voltage average based on each of the module voltages; Based on the third voltage threshold, the module voltage average and each module voltage, determining in sequence whether each battery module needs active balancing; When it is determined that the battery module needs active balancing, a DCDC module connected to the battery module is controlled to output a preset current to the battery module, so that the battery module performs the inter-module balancing control.

4. The battery cluster balancing control method according to claim 1, characterized in that: When performing the inter-module balancing control on each of the battery modules, the step of judging whether the cells of each module are balanced based on the second voltage threshold, the highest cell voltage and the lowest cell voltage among the cell voltages of the corresponding battery module comprises: When performing the inter-module balancing control on each of the battery modules, obtaining a maximum cell voltage difference based on the highest cell voltage and the lowest cell voltage; When the maximum cell voltage difference is greater than the second voltage threshold, determining that the cell of each module is unbalanced; Or, when the maximum cell voltage difference is not greater than the second voltage threshold, it is determined that the cells of each module are balanced.

5. The battery cluster balancing control method according to claim 1, characterized in that: When it is determined that the battery cells of each module are unbalanced, the step of performing battery cell balancing control on the battery cells of each module comprises: When it is determined that the battery cells of each module are unbalanced, based on the voltages of each battery cell of the corresponding battery module and the lowest battery cell voltage, a relative voltage difference of each battery cell is obtained; Based on the relative voltage difference of each battery cell and the second voltage threshold, determining in turn whether each module battery cell needs passive balancing; When it is determined that the module cells need passive balancing, the corresponding parallel switch devices of the module cells are controlled to be turned on, and the balancing resistors connected in series with the switch devices are connected to the module cells, so that the module cells can perform the balancing control between the cells.

6. The battery cluster balancing control method according to claim 1, characterized in that: After the step of judging whether the battery modules are balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, the method further includes: When determining that each of the battery modules is balanced, based on each of the battery cell voltages corresponding to the battery module, the highest battery cell voltage, and the lowest battery cell voltage, a maximum battery cell voltage difference and a relative voltage difference of each battery cell are obtained; Based on the maximum cell voltage difference, the relative voltage difference of each cell and the second voltage threshold, determining whether each module cell needs passive balancing; When it is determined that the module cells need passive balancing, the corresponding parallel switch devices of the module cells are controlled to be turned on, and the balancing resistors connected in series with the switch devices are connected to the module cells, so that the module cells can perform the balancing control between the cells.

7. The battery cluster balancing control method according to claim 1, characterized in that: Before the step of judging whether each of the battery modules is balanced based on the first voltage threshold, the highest module voltage and the lowest module voltage among the module voltages, the method further includes: Obtaining the number of cells in each of the battery modules; Based on the number of each of the battery cells and the second voltage threshold, the first voltage threshold corresponding to each of the battery modules is determined.

8. A battery cluster balancing control device, characterized in that: The battery cluster balancing control device comprises: A voltage acquisition module, used to acquire the voltage of each module of each battery module in the battery cluster, and acquire the voltage of each cell of each module cell in each of the battery modules; An inter-module balance judgment module, used for judging whether the battery modules are balanced based on a first voltage threshold, a highest module voltage and a lowest module voltage among the module voltages; An inter-module balancing control module, used for performing inter-module balancing control on each of the battery modules when it is determined that each of the battery modules is unbalanced; An inter-cell balancing judgment module, used for judging whether the cells of each module are balanced based on a second voltage threshold, a highest cell voltage and a lowest cell voltage among the cell voltages of each cell of the battery module when performing the inter-module balancing control on each battery module; The cell-to-cell balancing control module is used to perform cell-to-cell balancing control on the cell-to-cell of each module when it is determined that the cell-to-cell of each module is unbalanced.

9. A battery cluster balancing control device, characterized in that: The battery cluster balancing control device comprises: a memory, a processor, and a battery cluster balancing control program stored in the memory and executable on the processor, wherein the battery cluster balancing control program is configured to implement the steps of the battery cluster balancing control method according to any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, on which a battery cluster balancing control program is stored. When the battery cluster balancing control program is executed by a processor, the steps of the battery cluster balancing control method according to any one of claims 1 to 7 are implemented.

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